IMPROVING CARDIAC MRI-BASED INFARCT SIZING: LONG-AXIS IMPLEMENTATION AND INCREASED PRECISION OF AMERICAN HEART ASSOCIATION 17-SEGMENT BASED LEFT VENTRICLE INFARCT PERCENTAGE IN CARDIAC MAGNETIC RESONANCE IMAGE-BASED INFARCT

Abstract

Currently, physicians and research scientists use the American Heart Association (AHA) 17-segment model of Magnetic Resonance Imaging (MRI) as the preferred clinical method to define infarcted myocardial scar tissue and quantify myocardial infarction (MI) size [1]. The method is subjective and can be an inaccurate approximation of infarcted tissue quantity when compared to post-mortem histopathology, which is considered the gold standard. This study focuses on improving the accuracy, precision, and reproducibility of infarct volume quantification when measuring MRI-based images from a porcine model of ischemic heart failure. Data was collected from infarcted mini swine that underwent serial MRI over the course of 6 months and end point organ harvesting for histopathologic analysis. Methods improving infarct size quantification could potentially impact translational research studies with the expectation of improving patient care. By applying a modified long axis (LAX) MRI-based version of infarct sizing, adapted from histopathology-based infarct sizing, and implementing a long axis ratio (LAR) coefficient we propose a more accurate model to noninvasively quantify infarcted myocardial mass that will reduce subjective error and potentially improve clinical treatment strategies and patient outcomes.